Qualcomm, Allwinner & MediaTek All Go Octa

If there was any doubt about the potential for octa-core ARM-based processors, the flurry of announcements at MWC puts it to rest. Allwinner, MediaTek, and Qualcomm all announce 8-core SoCs for mobile devices. The new devices join octa-core solutions already available from MediaTek and Samsung.

If there was any doubt about the potential for octa-core ARM-based processors, the flurry of announcements at MWC will put that to rest. Allwinner, MediaTek, and Qualcomm all announce 8-core SoCs for mobile devices. The new devices join octa-core solutions already available from MediaTek and Samsung.

First up is Allwinner, which has aggressively entered the mobile SoC market and quickly differentiated itself from the other Chinese vendors by going after mid-range solutions. Allwinner announced the 32-bit UltraOcta A80 SoC featuring four ARM Cortex-A7s plus four ARM Cortex-A15s in ARM’s big.LITTLE configuration. The A80 also features the PowerVR Series 6 GPU in what appears to be a dual-core configuration from Imagination.

Next is MediaTek with the introduction of the company’s second 32-bit octa-core SoC, the MT6595. The MT6595 also features the ARM big.LITTLE configuration, but features four ARM Cortex-A7s combined with four ARM Cortex-A17s, ARM’s latest 32-bit CPU and one particularly aimed at mobile applications. The MT6595 also features Imagination’s PowerVR Series 6 GPU in a dual-core configuration plus all the wireless interfaces for a complete mobile SoC, including 802.11az (WiFi), GPS, Bluetooth, FM, ANT+, and full 4G LTE support in a single chip. Note that MediaTek previously announced the MT6592, which featured eight ARM Cortex A7s and the ARM Mali450 GPU. MediaTek also announced a quad-core 64-bit MT6732 using ARM Cortex-A53s.

Last but not least is a new and the only 64-bit octa-core, the Snapdragon 615 from Qualcomm. The 615 utilizes eight ARM Cortex-A53s configured into two quad-core clusters. One cluster is optimized at the silicon-level and frequency for power and the other for performance. Qualcomm is also offering a quad-core version called the Snapdragon 610, which is a step up in performance from the previously announced Snapdragon 410. The 615 and 610 also feature Qualcomm’s new Adreno 405 GPU. All of the new devices from Qualcomm are pin compatible and include Qualcomm’s 4G LTE cellular modem.

These join the Samsung Exynos 5 Octa, which features four ARM Cortex-A7s with four ARM Cortex-A15s, similar to the new Allwinner device, but with the previous generation PowerVR Series 5 GPU from Imagination.

All of the new devices are capable of handling 4k/H.264 video encode and decode, and are being positioned for high-end mobile devices, as well as other consumer applications. Unlike the rush to 64-bit with custom CPU cores, however, the rush to octa-core has all been around using standard synthesizable IP cores from ARM where SoC vendors can leverage the ARM big.LITTLE core configuration and/or rapid time to market.

Evaluating the different products on specs alone is rather challenging. According to ARM, the Cortex-A17 used in the MediaTek MT6595 provides a 60% performance boost over the Coretex-A9, but there is not a direct comparison to the A15 because the two devices are aimed at different segments of the market and have different architectural features. In addition, the ARMv8 64-bit architecture has significant enhancements over the ARMv7 32-bit architectures, but it’s not clear how a group of little 64-bit cores will compare in performance to a group of big 32-bit cores, especially when there are few 64-bit applications available. If that weren’t enough, each vendor has a different method of power gating the various CPU cores and different configurations for GPU cores. Measuring the performance of the various SoCs will have to wait until the devices using these SoCs are available, which should be starting in the second half of 2014. However, in terms of network connectivity, which is often overlooked in most performance evaluations, MediaTek and Qualcomm have the clear advantage.

I don't think anyone has tested A57 yet so that conclusion is not substantiated by evidence. AMD will have 8-core 2+GHz A57 SoCs on 28nm soon, and despite being a server part it uses less than 3W per core. A mobile version would use far less power without needing to be clocked at a lower frequency.

Anand seems to dislike A15, presumably because it beats Silvermont by a good amount. Given it will be running at 2.1-2.3GHz in mobile phones (at 28nm of course) the claims about A15 not being power efficient are false!

Also note NVidia K1 will be out at the end of the year, so even if A57 doesn't make it into mobiles by then, there will be high-end 64-bit ARM mobile SoCs available by then. It's quite obvious that Moorefield will not stand a chance - A57 is about twice as fast, and Denver will be faster still... This fall will be very interesting indeed!

tpfj - Customers, referring to both handset OEMs and carriers, do have specific requirements of their silicon providers. One request that has arisen from Asia is the increase in the number of cores. OEMs are still searching for a way to communicate performance and newness, and they like simple numbers like frequency and the number of cores. And who can blame them, the industry has programmed consumers to look for these numbers. In addition, the number "4" is deemed unlucky in Chinese custom, while the number "8" is deemed lucky, which is another factor OEMs don't face in other regions. As a result, look for a wide variety of solutions in the market that are aimed at not only cost and performance, but also marketing factors.

JimMcGregor, an interesting point you raise. Rather tangential, but do you think customers request features from silicon vendors and these are then architected by the vendor, or do you think silicon vendors try to read the market and architect things that they believe their customers want and then try to hard sell it to them?

My experience is more with the latter, but am no way saying that this is the way the industry works. I'm curious, what's your view?

jpfj - I think we need to log that one with the many other memorable industry quotes that were rather short sighted. Obviously, they would not spend the time to spin the silicon if their was not a customer request. Everyone is looking for some form of differentiation and that is leading to a plethora of SoC solutions.

The reason that al the current ARM parts are A53s is because many of the vendors are working on their own custom cores for the high-end, such as the custom core used in the Apple's A7 and the Denver core used in NVIDIA's Tegra K1, both of which are 64-bit cores. Apple was the first to production and NVIDIA will be in production this fall as well. Note that some vendors are also working on big.LITTLE configurations with the A53 and A57. You will also likely see more announcments in the coming months. And you are correct that Intel's Merrifield is also 64-bit, but not the only one. The real question is when will we see a 64-bit version of Android from Google?

Regarding the type and number of cores, there are many ways to build an SoC and many applications beyond just smartphones and tablets. Is 8-core overkill? At the time it may be, but then again, so is 64-bit without the applications. In fact, it is unlikely that you will be abl;e to use more than 4MB of memory in most handsets due to the size and power limitations.

Back in November, Anand talk to ARM about 64-bit. Arm said the A57 has more performance than the A15 but also uses more energy. Without 20nm, the A57 would have to be clocked much slower than the A15. Anand believed that would limit the A57 designs. Qualcomm today with the announcement of the A53 octa-cores proved Anand was right. The A57s are too hot to use at 28nm. It also shows that there will be very limited production of 20nm this fall and Qualcomm will more than likely not have a 20nm AP till 2015. At todays press conference, Qualcomm said that the A53 designs would be a S600 replacement as most applications do not use 8 cores. This leaves Intel's quad-core Moorefield as the only true top tier 64-bit Android SoC for the fall. This fall will be very interesting.